I think you wrote your problem wrong. I think it should be h+4/d = 5b
h+4=5b
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d
If I am correct, the answer is d=h+4/5b
you have to solve for d
since d is being divided by h+4, you will have to multiply both sides by d, which gives you
h+4=5bd Again, you have to solve for d, therefore you will have to divide both sides by 5b, which gives you h+4/5b=d